Environment/Climate Change
Dietary predictors of urinary metals concentrations in a cohort of Ugandan adolescent girls and young women Kristen Upson* Kristen Upson Upson Upson Upson Upson Upson Upson Upson Upson Upson Upson Department of Epidemiology and Biostatistics, College of Human Medicine, Michigan State University
Exposure to toxic metals can adversely affect health. The general population can be exposed through ingestion of contaminated food. To our knowledge, no studies have investigated dietary predictors of metal exposure in Uganda. We conducted a cross-sectional analysis using baseline data from the Kampala Women’s Bone Study. Young Ugandan women (n=499) ages 16-25 were enrolled in years 2018-2020. In urine samples, we measured arsenic (As), lead (Pb), mercury (Hg), nickel (Ni), and thallium (Tl) using inductively-coupled plasma-mass spectrometry; metal levels were specific gravity-adjusted to account for urinary dilution. Participants were asked about dietary intake of 22 food groups (both plant and non-plant-based) in the past week. In non-smokers (n=494), we conducted log-binomial regression to estimate the adjusted prevalence ratio (PR) and 95% CI for the associations between daily food intake (vs. none) and urinary metal levels ≥75th percentile, adjusting for age and education. We report aPRs ≥1.3 in magnitude with a confidence limit ratio ≤3. Our data suggested daily root tuber intake and higher Pb (PR 1.6 95%CI: 0.9-2.8) and Tl (PR 1.5 95%CI: 0.8-2.8). With daily rice intake, we observed higher As (PR 1.5 95%CI: 1.0-2.3) and Hg (PR 1.4 95%CI: 0.9- 2.1). Daily intake of sweets and confectionaries were associated with higher Pb (PR 1.5 95%CI: 1.0-2.3) and Hg (1.5 95%CI: 1.0-2.3). Higher Ni (PR 1.6 95%CI: 1.0-2.4) and Tl (PR 1.6 95%CI: 1.0-2.4) were observed with intake of dark greens on most days. As intake of whole grain cereal was low, we evaluated the consumption of any whole grain cereal which was associated with increased As (PR 1.4 95%CI: 1.0-2.0), Hg (PR 1.6 95%CI: 1.1-2.2) and Tl (PR 1.4 95%CI: 1.0-2.0). Our study suggests metal exposure with intake of plant-based foods. Plants can accumulate metals from contaminated soil and water. Further research is warranted to identify individual foods associated with metal exposure in Uganda and contamination sources.